IC card and booking-account system using the IC card

ABSTRACT

It is an object of the present invention to provide a highly sophisticated functional IC card that can ensure security by preventing forgery such as changing a picture of a face, and display other images as well as the picture of a face. An IC card comprising a display device and a plurality of thin film integrated circuits; wherein driving of the display device is controlled by the plurality of thin film integrated circuits; a semiconductor element used for the plurality of thin film integrated circuits and the display device is formed by using a polycrystalline semiconductor film; the plurality of thin film integrated circuits are laminated; the display device and the plurality of thin film integrated circuits are equipped for the same printed wiring board; and the IC card has a thickness of from 0.05 mm to 1 mm.

CROSS REFERENCE TO RELATED APPLICATIONS

Continuation of application Ser. No. 12/652,910, filed on Jan. 6, 2010,now U.S. Pat. No. 7,863,116, Continuation of application Ser. No.10/733,260, filed on Dec. 12, 2003, now U.S. Pat. No. 7,652,359.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an IC card (which is also called asmart card) incorporating an integrated circuit such as a memory or amicroprocessor (CPU). Further, the present invention relates to anbooking-account system of a dealing content in the case of using the ICcard as an ATM (automated teller machine) card (which is also called acash card).

2. Description of the Related Art

Several ten bytes of data only can be memorized in a magnetic card thatcan memorize data magnetically. However, an IC card incorporating asemiconductor memory, normally, can memorize about 5 KB of data or more.The IC card can assure much more capacity than a magnetic card. Further,the IC card has merits as follows: the IC card does not have a risk thatdata is read out by a physical means such as putting iron sand on acard, different from a magnetic card, and that data memorized in the ICcard is not easily falsified.

In recent years, an IC card has a highly sophisticated function by beingprovided with a CPU as well as a memory. The application thereof iswide-ranging, for example, an IC card is applied to an ATM card, acredit cart, a prepaid card, a patient's registration card, an identitycard such as a student card or an employee ID card, a season ticket, amembership card, etc. As an example of the highly sophisticatedfunction, an IC card for which a display device that can display simplecharacters and numbers is provided and for which a keyboard to inputnumbers is provided is described in the reference 1 (Reference 1:Japanese Examined Patent

As described in the Reference 1, a new use becomes possible by adding anew function to an ID card. Nowadays, electronic commerce, teleworking,remote medical care, remote education, computerized administrativeservices, automatic toll revenue from an expressway, image distributionservice and the like using an IC card are to be put to a practical useand it is considered that an IC card will be used in a wider field inthe future.

As an IC card is used more widely, a misapplication of an IC cardbecomes a bigger problem measurably. A future issue is how securelyidentification is performed when an IC card is used.

Printing a picture of a face in an IC card is one of measures forpreventing a misapplication of an IC card. It is possible, by printing apicture of a face, that a third person can identify a person to beidentified with a visual recognition when the person uses his/her ICcard, if such identification is not performed in an unattended terminaloperation such as ATM. A misapplication can be prevented efficiently inthe case where a security camera that can take a picture of a user'sface at close range is not provided.

However, in general, a picture of a face is transferred to an IC card bya printing method, and thus there is a pitfall that the picture of aface is easily changed by forgery.

The thickness of an IC card is generally 0.7 mm and the card is thin.Thus, it is necessary to provide a larger number of integrated circuitshaving a larger circuit scale or a larger memory capacity within thelimited area for sake of high-functionality when the area on which theintegrated circuit is provided is limited.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide a highlysophisticated functional IC card that can ensure security by preventingforgery such as changing a picture of a face, and that can display otherimages as well as a picture of a face.

According to the present invention, a display device which is thinenough to be accommodated within an IC card is equipped for the IC card.Specifically, an integrated circuit and a display device aremanufactured by a method described hereinafter.

A metal film is formed over a first substrate and a surface of the metalfilm is oxidized to form an ultrathin metal oxide film of several nm inthickness. An insulating film and a semiconductor film are laminated onthe metal oxide film sequentially. A semiconductor element to be usedfor an integrated circuit or a display device is manufactured by usingthe semiconductor film. In this specification, the integrated circuitused in the present invention is referred to as a thin film integratedcircuit hereinafter, for the purpose of distinguishing the integratedcircuit from an integrated circuit formed by using an existing siliconwafer. The semiconductor element is formed, and then, a second substrateis bonded so as to cover the element, thereby forming a state in whichthe semiconductor element is sandwiched between the first substrate andthe second substrate.

A third substrate is bonded to the opposite side of the semiconductorelement in the first substrate in order to enhance rigidity of the firstsubstrate. When the rigidity of the first substrate is higher than thatof the second substrate, the first substrate can be peeled off smoothlywith fewer damages to the semiconductor element. However, the thirdsubstrate is not always required to be bonded to the first substrate aslong as the rigidity of the first substrate is high enough when thefirst substrate is peeled off from the semiconductor element in a laterprocess.

The metal oxide film is crystallized by a heat treatment or the like toenhance brittleness thereof and make peeling of the substrate from thesemiconductor element easy. The first substrate and the third substrateare together peeled off from the semiconductor element. The heattreatment for crystallizing the metal oxide film may be performed beforebonding the third substrate or before bonding the second substrate.Alternatively, a heat treatment performed in a process of forming asemiconductor element may also serve as the process for crystallizingthe metal oxide film.

Three separated portions results from the peeling, that is, the portionin which the metal film is separated from the metal oxide film, theportion in which the insulating film is separated from the metal oxidefilm, or the portion in which the metal oxide film is separated to twosides itself. In any case, the semiconductor element is peeled off fromthe first substrate so that the semiconductor element can be bonded tothe second substrate.

After the first substrate is peeled off, the semiconductor element ismounted over a printed wiring board or an interposer to peel the secondsubstrate off. Note that, the second substrate is not always required tobe peeled off, when the thickness of the second substrate does notmatter. At the time, the semiconductor element to which the secondsubstrate is bonded may be complete.

A display element of a display device is manufactured after mounting thesemiconductor element over a printed wiring board or an interposer.Specifically, in the case of a liquid crystal display device, a pixelelectrode of a liquid crystal cell electrically connected to a TFT thatis one of semiconductor elements or an alignment film covering the pixelelectrode is formed and then, the semiconductor element, the pixelelectrode, and the alignment film are mounted over the printed wiringboard or the interposer. After that, an opposite substrate that wasmanufactured separately is bonded to the pixel electrode and thealignment film and a liquid crystal is injected to complete the liquidcrystal display device.

After the first substrate is peeled off, the semiconductor element maybe bonded to another substrate that becomes a base of the displaydevice, instead of bonding to the printed wiring board or theinterposer. After the display element is provided for the display deviceto complete the display device, the display device may be mounted overthe printed wiring board or the interposer together with the substratethat becomes a base. In this case, peeling of the second substrate isperformed before mounting. Preferably, the thickness of the substrateserving as a base is set to be thin enough not to prevent an IC cardfrom becoming thinner, specifically, to be several hundred μm or less.

An electrical connection (bonding) between the display device or thethin film integrated circuit formed by using the semiconductor elementand the printed wiring board or the interposer may be performed by aflip chip method, TAB (Tape Automated Bonding) method, or a wire-bondingmethod. When the flip chip method is employed, bonding and mounting areperformed at the same time. When a wire-bonding method is employed, thebonding process is performed in a state in which the second substrate ispeeled off after mounting.

When a plurality of thin film integrated circuits or display devices isformed on a substrate, dicing is performed halfway to separate the thinfilm integrated circuit or the display device. The timing for dicing isdifferent depending on whether a packaging of the thin film integratedcircuit is or not, or whether the substrate of the display deviceserving as a base is or not. In any case, the dicing is performed beforethe thin film integrated circuit or the display device is mounted orequipped for the printed wiring board.

When the thin film integrated circuit is packaged, a plurality of thinfilm integrated circuits is mounted on the same interposer to be used asa MCP. In this case, a wire-bonding method for electrical connectionbetween thin film integrated circuits or a flip chip method may beemployed.

The interposer may be connected electrically to a printed wiring boardby a lead frame or by a bump. Or the interposer may have another knownform.

According to the present invention, an ultrathin film integrated circuithaving a total thickness of from 1 μm through 5 μm, typically, 2 μm canbe formed by using a thin semiconductor film having a film thickness of500 nm or less, although an integrated circuit formed using a siliconwafer has a thickness of about 50 μm. The thickness of a display devicecan be set to about 0.5 mm, preferably, about 0.02 mm. Accordingly, itis possible to provide a display device for an IC card having athickness of from 0.05 mm through 1 mm. It is also possible to provide alarger number of thin film integrated circuits having a larger circuitscale or a larger memory capacity within the limited area, therebyrealizing multi-functionality of the IC card without preventingminiaturization and weight saving of the IC card.

According to the present invention, a glass substrate that is lessexpensive and larger than a silicon wafer can be used, and thus, thinfilm integrated circuits can be mass-produced at low cost and with highthroughput. As a result, a manufacturing cost can be reduceddramatically. Further, it is possible to use a substrate repeatedly,thereby reducing the cost.

The thin film integrated circuit does not need a back-grinding process,different from an integrated circuit formed by using a silicon wafer.The back-grinding process results in a crack or a grinding mark.Unevenness of the thickness depends on unevenness of each film making upa thin film integrated circuit in a film forming process, and thus, atmost several hundred nm of unevenness can be seen. The unevenness can besuppressed dramatically, as compared with the unevenness of several toseveral tens μm due to the back-grinding process.

A thin film integrated circuit or a display device can be bonded inaccordance with a shape of a printed wiring board, and thus, there is alot of flexibility for a shape of an IC card. Therefore, for example, itis possible to form an IC card into a shape having a curved surface,which can be attached to a columnar bottle.

The thin film integrated circuit is not limited to a mode in which thethin film integrated circuit is directly equipped for a printed wiringboard as a bare chip. The thin film integrated circuit can adopt a modein which the thin film integrated circuit is mounted on an interposer,packaged and equipped. A smaller and lighter thin film integratedcircuit can be obtained by being equipped a thin film integrated circuitas a bare chip. On the other hand, equipment can be performed easily bybeing equipped after packaging, without requiring a clean room or aspecial technology or facility such as a bonder when a thin filmintegrated circuit provided by a packaging manufacturer is equipped onan electronic device manufacturer side. The thin film integrated circuitcan be protected from an external environment, standardization of afootprint of a printed wiring board can be realized, wirings of a thinfilm integrated circuit on a sub micron scale can be enlarged to almostthe same millimeter scale as a printed wiring board.

The package can adopt various known modes such as DIP (Dual In-linePackage), QFP (Quad Flat Package), SOP (Small Outline Package), or thelike in addition to CSP (Chip Size Package), MCP (Multi Chip Package).

A liquid crystal display device, a light emitting device including alight emitting element typified by an organic light emitting element ineach pixel, a DMD (Digital Micromirror Device), or the like can beemployed as the display device. A microprocessor (CPU), a memory, apower source circuit, another digital circuit or analog circuit can beprovided for the thin film integrated circuit. A driver circuit of thedisplay device or a controller that generates a signal to be supplied tothe driver circuit may be provided within the thin film integratedcircuit.

The present invention is not limited to a card. The category of thepresent invention includes a portable recording medium that includes thethin film integrated circuit and the display device described above andthat can transmit and receive data with a host.

BRIEF DESCRIPTION OF THE DRAWINGS

In the accompanying drawings:

FIGS. 1A to 1C show an external view and an internal structure of an ICcard according to the present invention;

FIGS. 2A to 2C are enlarged views of a connection terminal and a thinfilm integrated circuit and an enlarged view of a connection portionbetween a display device and a printed wiring board;

FIGS. 3A to 3E show a method for manufacturing a semiconductor element;

FIGS. 4A to 4C show a method for manufacturing a semiconductor element;

FIGS. 5A to 5C show a method for manufacturing a semiconductor element;

FIG. 6 is a cross-sectional view of a liquid crystal display device;

FIG. 7 is a block diagram of a thin film integrated circuit and adisplay device;

FIGS. 8A to 8C show an internal structure of an IC card according to thepresent invention;

FIG. 9 is a block diagram of a thin film integrated circuit and adisplay device;

FIGS. 10A and 10B are block diagrams showing structures of an inputinterface and an output interface;

FIGS. 11A to 11D are cross-sectional views showing a structure of a thinfilm integrated circuit;

FIG. 12 shows how to use an IC card of the present invention;

FIGS. 13A to 13F show a method for manufacturing a display deviceaccording to the present invention; and

FIGS. 14A and 14B are cross-sectional views of a liquid crystal displaydevice.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Embodiment Mode

FIG. 1A shows a top view of an IC card according to the presentinvention. The IC card shown in FIG. 1A is a contact type card forsending and receiving data by electrically connecting a connectionterminal provided for the IC card to a reader/writer of terminalequipment. However, the IC card may be a noncontact type card forsending and receiving data without being connected.

Reference number 101 shows a card body. Reference number 102 correspondsto a pixel portion of a display device provided for the card body 101.Reference number 103 corresponds to a connection terminal of a thin filmintegrated circuit also provided for the card body 101.

FIG. 1B shows a structure of a printed wiring board 104 sealed withinthe card body. FIG. 1C shows a backside structure of the printed wiringboard 104 shown in FIG. 1B. A display device 105 is equipped for oneside of the printed wiring board 104 and a thin film integrated circuit106 is equipped for the other side thereof.

In the IC card shown in FIGS. 1A to 1C, the display device 105 and thethin film integrated circuit 106 are equipped for different sides of theprinted wiring board 104. However, the both may be equipped for the sameside. As shown in FIGS. 1A to 1C, when the display device 105 and thethin film integrated circuit 106 are equipped for different sides of theprinted wiring board 104, a lead (wiring) 108 electrically connected tothe display device 105 and a lead (wiring) 109 electrically connected tothe thin film integrated circuit 106 are electrically connected to eachother through a contact hole 107.

The connection terminal 103 is a terminal for sending and receiving databetween the terminal equipment and the IC card by being directlyconnected to a reader/writer provided for the terminal equipment. FIG.2A shows an enlarged view of the connection terminal 103 shown in FIG.1B. FIG. 2B shows an enlarged view of the thin film integrated circuit106 shown in FIG. 1C.

FIG. 2A shows an example in which eight connection terminals 103 areprovided for one side of the printed wiring board 104. However, thenumber of the connection terminals is not limited thereto, of course.Further, as shown in FIG. 2B, multiple pads 111 are provided for theother side of the printed wiring board 104.

The pad 111 is electrically connected to the thin film integratedcircuit 106 by a wire 112. The pad 111 is a pad that is electricallyconnected to the connection terminal 103 through a contact hole 110provided for the printed wiring board 104, or a pad that is electricallyconnected to the lead 109. A pad 111 that is electrically connected tothe connection terminal 103 or the lead 109, but that is notelectrically connected to the thin film integrated circuit 106 withoutproviding the wire 112 may be provided in some cases.

FIG. 2C shows a cross-sectional view of a portion in which the displaydevice 105 and the lead 108 are connected to each other. As shown inFIG. 2C, a terminal 114 provided for the display device 105 and the lead108 are electrically connected to each other by a wire 113, and the lead108 is electrically connected to a lead 109 through the contact hole107.

In this embodiment mode, the electrical connection between the pad 111and the thin film integrated circuit 106 is made by a wire-bondingmethod. However, the present invention is not limited to the method. Aflip chip bonding method using a solder ball or other method may beemployed for the connection, and other methods may be employed for theelectrical connection. The method for electrically connecting thedisplay device 105 to the lead 108 is not limited to the wire-bondingmethod, and other methods may be employed for the electrical connection.

The electrical connection between the connection terminal 103 and thethin film integrated circuit 106 is not limited to the mode of thepresent embodiment mode. For example, the connection between theconnection terminal and thin film integrated circuit may be conducteddirectly by a wire through a contact hole, without providing a pad.

A method for manufacturing a thin film integrated circuit is described,and then a method for manufacturing a display device is described. Notethat, in this embodiment mode, although two TFTs are given as an exampleof a semiconductor element, the semiconductor element included in thethin film integrated circuit and the display device is not limitedthereto, and various circuit elements can be used. For example, a memoryelement, a diode, a photoelectric transferring element, a resistorelement, a coil, a capacitor element, or an inductor can be given as arepresentative example in addition to a TFT.

As shown in FIG. 3A, a metal film 501 is formed on a first substrate 500by sputtering. The metal film 501 is formed of tungsten to be 10 nm to200 nm, preferably 50 nm to 75 nm in thickness. In this embodiment mode,the metal film 501 is formed directly on the first substrate 500.However, the first substrate 500 may be covered with an insulating filmsuch as a silicon oxide, a silicon nitride, a silicon nitride-oxide andthen, the metal film 501 may be formed thereover.

After the metal film 501 is formed, an oxide film 502 is formed to belaminated over the metal film 501 without being exposed to air. Asilicon oxide film is formed to be 150 nm to 300 nm in thickness as theoxide film 502. When the sputtering method is employed, an edge face ofthe first substrate 500 is also deposited. Therefore, preferably, themetal film 501 and the oxide film 502 deposited in the edge face areselectively removed by O₂ ashing or the like in order to prevent theoxide film 502 from remaining on the side of the first substrate 500 ina later process for peeling off.

When the oxide film 502 is formed, a pre-sputtering for generatingplasma by blocking a target from a substrate with a shutter is conductedas a preliminary step toward sputtering. The pre-sputtering is conductedunder conditions where the flow rates of Ar and O₂ are set to 10 sccmand 30 sccm, respectively, the temperature of the first substrate 500 isset to 270° C., and deposition power is kept 3 kW in an equilibriumsituation. An ultrathin metal oxide film 503 of several nm (here, 3 nm)is formed between the metal film 501 and the oxide film 502. The surfaceof the metal film 501 is oxidized to form the metal oxide film 503.Accordingly, the metal oxide film 503 is made of tungstic oxide in thisembodiment mode.

In this embodiment mode, the metal oxide film 503 is formed by thepre-sputtering. However, the present invention is not limited to themethod. For example, the metal oxide film 503 may be formed by oxidizingdeliberately the surface of the metal film 501 by plasma in theatmosphere of oxygen or oxygen added with inert gases such as Ar.

After forming the oxide film 502, a base film 504 is formed by PCVD.Here, a silicon oxynitride film is formed to have a thicknessapproximately of 100 nm as the base film 504. After forming the basefilm 504, a semiconductor film 505 is formed without being exposed toair. The semiconductor film 505 is formed to have a thickness of from 25nm to 100 nm (preferably from 30 nm to 60 nm). The semiconductor film505 may be an amorphous semiconductor or a polycrystallinesemiconductor. Silicon germanium as well as silicon may be used for asemiconductor. In the case of using silicon germanium, the concentrationthereof is preferably approximately from 0.01 atomic % to 4.5 atomic %.

As shown in FIG. 3B, the semiconductor film 505 is crystallized by aknown technique. As known methods of crystallization, there are athermal-crystallization method using an electric heater, a laserannealing crystallization method using a laser beam, and a lampannealing crystallization method using an infrared ray. Alternatively, acrystallization method using a catalytic element may be conductedaccording to a technique described in Japanese Patent Laid Open No.H07-130652.

The semiconductor film 505 that is a polycrystalline semiconductor filmmay in advance be formed by a sputtering method, a plasma CVD method, athermal CVD method, or the like.

In this embodiment mode, the semiconductor film 505 is crystallized by alaser crystallization. It is possible to obtain crystals having a largegrain size by emitting a laser beam of second to fourth harmonics of afundamental harmonic with a solid-state laser that is capable ofcontinuously emitting. Typically, it is preferable to use secondharmonic (532 nm) or third harmonic (355 nm) of Nd:YVO₄ laser(fundamental harmonic: 1064 nm). Specifically, a laser beam emitted fromcontinuous wave type YVO₄ laser is converted to the harmonic with anon-linear optical element to obtain the output power of 10 W. Further,there is a method of emitting a harmonic with a non-linear opticalelement. Preferably, the laser beam is formed to have a rectangularshape or an elliptical shape in a surface to be irradiated by using anoptical system. The semiconductor film 505 is irradiated with theabove-described laser beam. On this occasion, an energy density ofapproximately from 0.01 MW/cm2 to 100 MW/cm² (preferably from 0.1 MW/cm²to 10 MW/cm²) is necessary. The scanning speed thereof is set toapproximately from 10 cm/s to 2000 cm/s for emitting the laser beam to adirection indicated by an arrow.

The laser crystallization may be conducted by emitting laser beams of afundamental wave and a harmonic of a continuous wave, or emitting alaser beam of a fundamental wave of a continuous wave and a laser beamof a harmonic of a pulsed laser.

A laser beam may be emitted in the inert gas atmosphere such as noblegas or nitride. According to this, the surface roughness of asemiconductor due to laser beam irradiation, and further, fluctuation ina threshold value due to the variations of interface state density canbe prevented.

A semiconductor film 506 whose degree of crystallinity is enhanced bythe above described laser irradiation on the semiconductor film 505 isformed. Then, as shown in FIG. 3C, the semiconductor film 506 ispatterned to form island shape semiconductor films 507 and 508. Varioussemiconductor elements as typified by a TFT are formed using the islandshape semiconductor films 507 and 508. In this embodiment mode, theisland shape semiconductor films 507 and 508 are in contact with thebase film 504, but an electrode, an insulating film, or the like may beformed between the base film 504 and the island shape semiconductorfilms 507 and 508 depending on a semiconductor element. For example, inthe case of a bottom gate TFT that is one of the semiconductor elements,a gate electrode and a gate insulating film are formed between the basefilm 504 and the island shape semiconductor films 507 and 508.

In this embodiment mode, top gate TFTs 509 and 510 are formed using theisland shape semiconductor films 507 and 508 (FIG. 3D). Specifically, agate insulating film 511 is formed so as to cover the island shapesemiconductor films 507 and 508. Then, a conductive film is formed overthe gate insulating film 511 and patterned, and thus, gate electrodes512 and 513 are formed. Next, impurities imparting n-type are added tothe island shape semiconductor films 507 and 508 by using the gateelectrodes 512 and 513 or a resist that is formed and patterned as amask to form a source region, a drain region, an LDD (Lightly DopedDrain) region and the like. Here, TFTs 509 and 510 are n-type, butimpurities imparting p-type are added in the case of using p-type TFTs.

According to the above-described process, TFTs 509 and 510 can beformed. A method for manufacturing the TFTs is not limited to theabove-described process.

A first interlayer insulating film 514 is formed so as to cover the TFTs509 and 510. Contact holes are formed in the gate insulating film 511and the first interlayer insulating film 514, and then, wirings 515 to518 connected to the TFTs 509 and 510 through the contact holes areformed so as to be in contact with the first interlayer insulating film514. A second interlayer insulating film 519 is formed over the firstinterlayer insulating film 514 so as to cover the wirings 515 to 518.

A contact hole is formed in the second interlayer insulating film 519,and a terminal 520 to connect to the wiring 518 through the contact holeis formed over the second interlayer insulating film 519. In thisembodiment mode, the terminal 520 is electrically connected to the TFT510 through the wiring 518, but the electrical connection between thesemiconductor element and the terminal 520 is not limited thereto.

A protective layer 521 is formed over the second interlayer insulatingfilm 519 and the terminal 520. As a material for forming the protectivelayer 521, a material which can protect the surfaces of the secondinterlayer insulating film 519 and the terminal 520 and which can beremoved after peeling off a second substrate is used, in a later processof bonding or peeling off the second substrate. For example, theprotective layer 521 can be formed by coating an epoxy-, acrylate-, orsilicon-based resin that is soluble in water or alcohol over the wholesurface and baking.

In this embodiment mode, water-soluble resin (TOAGOSEI Co., Ltd.:VL-WSHL10) is spin-coated to have a thickness of 30 μm, and exposed fortwo minutes to be pre-cured, then, exposed its back to UV rays for 2.5minutes, and then, exposed its surface for 10 minutes, namely total 12.5minutes to be fully cured. Consequently, the protective layer 521 isformed (FIG. 3E).

In the case of stacking a plurality of organic resins, there is a riskof melting partially the stacked organic resins depending on the usedsolvent during coating or baking, or increasing the adhesion thereofexcessively. Therefore, in the case of using both the second interlayerinsulating film 519 and the protective layer 521 of organic resins thatare soluble in the same solvent, an inorganic insulating film (a SiN_(X)film, a SiN_(X)O_(Y) film, an AlN_(X) film, or an AlN_(X)O_(Y) film) ispreferably formed to cover the second interlayer insulating film 519 soas to remove smoothly the protective film 521 in a later process, and beinterposed between the second interlayer insulating film 519 and theterminal 520.

The metal oxide film 503 is crystallized for peeling smoothly in a laterprocess. The metal oxide film 503 becomes susceptible to cleave at agrain boundary and its brittleness is enhanced by the crystallization.In this embodiment mode, the crystallization is carried out by heattreatment for approximately from 0.5 hours to 5 hours at temperaturesfrom 420° C. to 550° C.

Then, some treatments are carried out on the metal oxide film 503 inorder to make a portion that can spark the start of peeling-off byweakening partly the adhesion between the metal oxide film 503 and theoxide film 502 or the adhesion between the metal oxide film 503 and themetal film 501. Specifically, a part of the inside or a part of thevicinity of the interface of the oxide film 503 is damaged by pressuringlocally from outside on the metal oxide film 503 along with theperiphery of a region to be separated. Specifically, a hard needle suchas a diamond pen may be perpendicularly pressed on the periphery of theedge portion of the metal oxide film 503 and moved along the metal oxidefilm 503 with applying loading. Preferably, a scriber device can be usedto move the pen with applying loading with press force ranging from 0.1mm to 2 mm. As described above, a portion having weakened adhesion thatcan spark the start of peeling-off is formed before the peeling-off ispreformed, thereby preventing poor peeling-off in a later process of thepeeling-off and improving the process yield.

Next, a second substrate 523 is pasted over the protective layer 521with a two-sided tape 522, and a third substrate 525 is pasted over thefirst substrate 500 with a two-sided tape 524 (FIG. 4A). An adhesiveagent may be used instead of the two-sided tape. For example, it ispossible to reduce the load that is applied to the semiconductor elementin peeling off the second substrate by using an adhesive agent that ispeeled off by UV light. The third substrate 525 prevents the destructionof the first substrate 500 in a later peeling-off process. For thesecond substrate 523 and the third substrate 525, the substrate that hashigher rigidity than that of the first substrate 500, for example, aquartz substrate or a semiconductor substrate is preferably to be used.

Then, the metal film 501 is separated from the oxide film 502 by aphysical means. The peeling-off of the metal film 501 is started fromthe region in which adhesion of the metal oxide film 503 to the metalfilm 501 or the oxide film 502 is partly weakened in the previousprocess.

Three separated portions results from the peeling-off of metal film 501,that is, a portion in which the metal film 501 is separated from metaloxide film 503, a portion in which the oxide film 502 is separated fromthe metal oxide film 503, or a portion in which the metal oxide film 503is itself separated to two sides. Further, the second substrate 523 onwhich semiconductor elements (here, TFTs 509 and 510) are pasted isseparated from the third substrate 525 on which the first substrate 500and the metal film 501 are pasted. The peeling-off can be carried outwith comparatively small force (for example, man's power, air pressureof gas sprayed from a nozzle, ultrasonic waves, or the like). FIG. 4Bshows a state after the peeling-off process.

A printed wiring board 527 is bonded to the oxide film 502 to a part ofwhich the metal oxide film 503 is attached with an adhesive agent 526(FIG. 4C). In this embodiment mode, an example of equipping a thin filmintegrated circuit for a printed wiring board as a bare chip isdescribed. However, in the case of equipping after packaging, a thinfilm integrated circuit is mounted over an interposer.

In the adhesive bonding, it is important to select a material for theadhesive agent 526 so that adhesion degree between the oxide film 502and the printed wiring board 527 by the adhesive agent 526 is higherthan that between the second substrate 523 and the protective layer 521by the two-sided tape 522.

Note that, in some cases, the adhesion with the printed wiring board 527becomes worse since the metal oxide film 503 is left in a surface of theoxide film 502. For the sake of preventing that, the metal oxide film503 may be removed completely by etching or the like, and then, bondedto the printed wiring board to enhance the adhesion.

As a material for the printed wiring board 527, a known material such asa ceramic substrate, a glass epoxy substrate, and a polyimide substratecan be used. The material preferably has high thermal conductivity ofapproximately from 2 W/mK to 30 W/mK for radiating heat generated in athin film integrated circuit or a display device.

A pad 530 is provided over the printed wiring board 527. The pad 530 is,for example, formed of copper plated with solder, gold, or tin.

As the adhesive agent 526, various curing adhesives such as aphoto-curing adhesive, for example, a reaction-curing adhesive, athermal-curing adhesive, or a UV-curing adhesive, and an anaerobicadhesive can be used. The adhesive agent 526 is preferably given highthermal conductivity by being mixed with powder comprising silver,nickel, aluminum, or aluminum nitride, or filler.

As shown in FIG. 5A, the two-sided tape 522 and the second substrate 523are separated sequentially or simultaneously from the protective layer521.

As shown in FIG. 5B, the protective film 521 is removed by water sincethe protective film 521 is formed of the resin that is soluble in water.In the case where the left protective film 521 causes deterioration, theleft protective film 521 is preferably removed by carrying out cleaningtreatment or O₂ plasma treatment on the surface after the removingprocess.

The terminal 520 is connected to the pad 530 with a wire 532 by awire-bonding method as shown in FIG. 5C. Mounting and electricallyconnecting are performed to complete the equipment.

Note that, in the case where the thin film integrated circuit is mountedover an interposer, and then packaged, a hermetic sealing manner,plastic molding manner, or the like can be employed for sealing. In thecase of using the hermetic sealing manner, a case made of ceramic,metal, glass, or the like is generally used for the sealing. In case ofusing the plastic molding manner, a mold resin or the like isspecifically used. Although it is not always necessary to seal the thinfilm integrated circuit, the sealing offers some advantages of enhancingstrength of the package, radiating heat generated in the thin filmintegrated circuit, and shielding electromagnetic noises from adjacentcircuits.

In this embodiment mode, tungsten is used for the metal film 501,however, the present invention is not limited thereto. Any material canbe used as long as the material includes a metal that allows a substrateto be peeled off by forming the metal oxide film 503 over the surface ofthe material and crystallizing the metal oxide film 503. For example,TiN, WN, Mo or the like as well as W can be used. When alloy of theelements is used as a metal film, the optimum temperature for a heattreatment in crystallization is different depending on the compositionratio thereof. Accordingly, the heat treatment can be performed at atemperature that is not interference in the process for manufacturing asemiconductor element by adjusting the composition ratio, and therefore,there are few limitations in choices for the process for a semiconductorelement.

In the laser crystallization, each thin film integrated circuit isformed in a region which is within a width in a direction perpendicularto the scanning direction of a beam spot of laser beam, which preventsthe thin film integrated circuits from being exposed to the beam ofregions having poor crystallinity (edges) at both end portions of thelongitudinal axis of the beam spot. According to this, a semiconductorfilm having few crystal grain boundaries can be used for a semiconductorelement in the thin film integrated circuit.

According to the above-described method, a ultrathin film integratedcircuit can be formed to be 1 μm to 5 μm in a total thickness,typically, about 2 μm. The thickness of the thin film integrated circuitincludes a thickness of an insulating film provided between the metaloxide film and the semiconductor element, a thickness of an interlayerinsulating film to cover the formed semiconductor element, and athickness of terminals in addition to the thickness of the semiconductorelement itself.

Next, a method for manufacturing a display device according to thepresent invention is described.

FIG. 6 shows a cross sectional view showing a display device 6002 whichis mounted over a printed wiring board 6000 by an adhesive agent 6001.In FIG. 6, the display device 6002 is a liquid crystal display device asan example.

In the display device 6002 shown in FIG. 6, up to the process for makinga semiconductor film is performed according to the method shown in FIG.3A. A TFT 6003 made by using the semiconductor film, a passivation film6015 made of an inorganic insulating film, an insulating film 6005covering the TFT 6003, a pixel electrode 6004 that is electricallyconnecting to the TFT 6003 and formed over the insulating film 6005, aterminal 6006 for the display device 6002, which is formed over theinsulating film 6005, an alignment film 6007 covering the pixelelectrode 6004 are formed. The alignment film 6007 is exposed to arubbing treatment. A spacer 6008 may be formed using an insulating filmbefore the alignment film 6007 is formed. The terminal 6006 is exposedwithout being covered with the alignment film 6007.

A protective film is formed over the alignment film 6007 according tothe method shown in FIG. 3E. The semiconductor element is mounted overthe printed wiring board, and the second substrate and the protectivefilm are removed, after peeling off the first substrate according to theprocesses shown in FIGS. 4A to 4C and FIGS. 5A and 5B.

An opposite substrate 6009 formed separately is bonded to the alignmentfilm 6007 by a sealing material 6010. A filler may be mixed into thesealing material. The opposite substrate 6009 has a structure in whichan opposite electrode 6012 comprising a transparent conductive film andan alignment film 6013 exposed to a rubbing treatment are formed overthe substrate 6011 having a thickness of about several hundred μm.Further, a color filter or a blocking layer for preventing disclinationmay be provided for the opposite substrate. A polarization plate 6014 isbonded to a reverse face of the opposite electrode 6012 in the oppositesubstrate 6009.

A plastic substrate can be used for the substrate 6011. ARTON(manufactured by JSR corporation) comprising a norbornene resinincluding a polar group can be used for the plastic substrate.Polyethylene terephthalate (PET), polyether sulfone (PES), polyethylenenaphthalate (PEN), polycarbonate (PC), nylon, polyetheretherketone(PEEK), polysulfone (PSF), polyetherimide (PEI), polyarylate (PAR),polybutylene telephthalate (PBT), or polyimide can be used for theplastic substrate.

A liquid crystal 6025 is injected and sealed in to complete a displaydevice. The terminal 6006 for the display device 6002 is electricallyconnected to a lead provided for the printed wiring board 6000 by awire-bonding method or the like to finish the equipment.

In this embodiment mode, the semiconductor element is mounted over theprinted wiring board after peeling off the first substrate in theprocess for manufacturing the display device. However, the presentinvention is not limited thereto. Another substrate serving as a base ofthe display device is provided separately and then, the display deviceis bonded to the substrate serving as a base, after peeling off thefirst substrate. The display device together with the substrate servingas a base may be mounted over the printed wiring board. In this case, itis possible to mount the display device over the printed wiring boardafter the display device is completed. That is, in the case of a liquidcrystal display device, it is possible to mount the display device overthe printed wiring board after the display device is completed byinjecting a liquid crystal and sealing. For example, it is difficult tomanufacture a light emitting element that is a display element in aprinted wiring board since formations of electroluminescence layer,cathode and the like are included in the case of the light emittingdevice. Accordingly, it is efficient to mount the display device over aprinted wiring board after the display device is completed by using thesubstrate serving as a base in the case of the light emitting device.

The liquid crystal display device shown in FIG. 6 is reflective type. Aslong as a backlight can be provided for the liquid display device, itmay be a transmissive type. When the reflective liquid crystal displaydevice is used, it is possible to reduce power consumption required fordisplaying an image more, as compared with a transmissive one. However,when the transmissive liquid crystal display device is used, an imagecan be seen more easily in the dark, as compared with the reflectiveone.

The display device of the present invention is required to have a highresolution enough that a person can be recognized with a photograph ofthe person's face. Therefore, for the sake of using the display deviceinstead of an identification photograph, at least QVGA (320×240) ofresolution is to be required.

The printed wiring board is sealed with a sealant after the equipment ofthe thin film integrated circuit and the display device for the printedwiring board is completed. Materials used generally can be used forsealing the card, for example, polymeric material such as polyester,acrylic acid, polyvinyl acetate, propylene, chloroethene,acrylonitrile-butadiene-styrene resin, or polyethylene terephthalate canbe used. When the sealing is performed, the pixel portion of the displaydevice is exposed. In the case of a contact type IC card, the connectionterminals as well as the pixel portion are exposed. The IC card havingan appearance shown in FIG. 1A can be formed by the sealing.

Next, one mode of a thin film integrated circuit and a display device isdescribed. FIG. 7 shows a block diagram of a thin film integratedcircuit 201 and a display device 202 mounted over the IC card of thepresent invention.

Signals are sent and received via an interface 203 provided for the thinfilm integrated circuit 201 between the thin film integrated circuit 201and a connection terminal 215 provided for the printed wiring board. Apower supply voltage from the connection terminals 215 is supplied tothe thin film integrated circuit 201 via the interface 203.

A CPU 204, a ROM 205, a RAM 206, an EEPROM 207, a coprocessor 208, and acontroller 209 are provided for the thin film integrated circuit 201shown in FIG. 7.

All processes of the IC card are controlled by the CPU 2004. Eachprogram used in the CPU 204 is memorized in the ROM 205. The coprocessor208 is a secondary coprocessor for helping with operation of the mainCPU 204. The RAM 206 is used as an operation area during data processingas well as a buffer during a communication of terminal equipment and thethin film integrated circuit film 201. The EEPROM 207 can memorize datainputted as a signal in a determined address.

Note that, image data such as a photograph of a face is memorized in theEEPROM 207 when the data can be rewritten, and in the ROM 205 when thedata cannot be rewritten. Alternatively, another memory for memorizingimage data may be provided.

A signal including image data is exposed to data processing inaccordance with a specification of the display device 202 and suppliedto the display device 202 as a video signal by the controller 209. AnHsync signal, Vsync signal, clock signal CLK, and an alternating voltage(AC Cont), etc. are generated based on respective signals or powersupply voltage inputted from the connection terminals 215 and aresupplied to the display device 202 by the controller 209.

A pixel portion 210 in which a display element is provided for eachpixel, a scanning line driver circuit 211 for selecting a pixel providedfor the pixel portion 210, and a signal line driver circuit 212 forsupplying a video signal to the selected pixel are provided for thedisplay device 202.

The structure, shown in FIG. 7, of the thin film integrated circuit 201and the display device 202 is one example. The present invention is notlimited to the structure. The display device 202 may include a functionfor displaying an image, and be an active type or a passive type. Thethin film integrated circuit 201 may include a function for supplying asignal for controlling the driving of the display device 202 to thedisplay device 202.

It is possible to make changing a photograph of a human face moredifficult by displaying data of human face in the display device, ascompared with the case of using the printing method. It is also possibleto prevent a card forgery and ensure a security of an IC card bymemorizing the data of human face in a memory such as ROM in which datacannot be rewritten. Further, more ensured prevention of forgery can beobtained by configuring the card so that ROM is broken when the IC cardis tore down forcibly.

A semiconductor film, an insulating film or the like used in a displaydevice is incused with a serial number. If a third person gets illegallyan stolen IC card in which image data is not memorized in a ROM, it ispossible to trace the distribution route by the serial number to someextent. In this case, it is efficient to incuse a serial number in apart in which the serial number can be deleted, only when the displaydevice is tore down irreparably and cannot be repaired.

The IC card of the present invention is much thinner than that of a thinfilm integrated circuit manufactured using a silicon wafer, and thus,much more thin film integrated circuit film can be laminated andequipped in the limited area. Accordingly, it is possible to make acircuit scale or memory capacity larger keeping the area of the thinfilm integrated circuit laid out over a printed wiring board suppressed,thereby making the IC card have a more sophisticated function.

A plastic substrate has a poor heat resistance up to a temperature inthe manufacturing process of a semiconductor element, and is difficultto use. However, according to the present invention, a glass substrate,silicon wafer or the like having relatively high heat resistance up to atemperature in the manufacturing process including a heat treatment isused and a semiconductor element can be transported to a plasticsubstrate, after the manufacturing process is finished. As a result, aplastic substrate that is thinner than a glass substrate or the like canbe employed. Although a display device formed over a glass substrate hasa thickness of at most 2 mm to 3 mm, a display device can have athickness of approximately 0.5 mm, preferably 0.02 mm by using a plasticsubstrate, and thus the display device becomes much thinner dramaticallyaccording to the present invention. The display device can be made muchthinner, thereby making it possible to provide the thin film integratedcircuit and the display device for an IC card and to make the IC cardhave a highly sophisticated function.

An IC card of the present invention is not limited to a contact typecard, but may be a noncontact type card. A structure of an IC card ofthe present invention is described with reference to FIGS. 8A to 8C.

FIG. 8A shows a structure of a printed wiring board 301 that is sealedin a noncontact type IC card. As shown in FIG. 8A, a display device 302and a thin film integrated circuit 303 are equipped for the printedwiring board 301, and the display device 302 is electrically connectedto the thin film integrated circuit 303 by a lead 304. In FIG. 8A, thethin film integrated circuit 303 and the display device 302 are equippedtogether for one side of the printed wiring board 301. However, thepresent invention is not limited thereto. The display device 302 may beequipped for one side the printed wiring board 301, and the thin filmintegrated circuit 303 may be equipped for the other side thereof.

FIG. 8B shows a structure of a backside of the printed wiring board 301shown in FIG. 8A. As shown in FIG. 8B, an antenna coil 305 is equippedfor the printed wiring board 301. Sending and receiving data between thethin film integrated circuit 303 and a terminal equipment can beperformed using electromagnetic induction by the antenna coil 305without having a contact. As a result, the IC card is suffered from lessphysical wear or damage than a contact type IC card.

FIG. 8B shows an example of using the printed wiring board 301incorporating the antenna coil 305. However, an antenna coil that ismade separately may be equipped for the printed wiring board 301. Forexample, copper wire is wound in coil form and sandwiched between twoplastic films having a thickness of about 100 μm and pressed, which canbe used as an antenna coil.

In FIG. 8B, one antenna coil 305 is used for one IC card. However, aplurality of antenna coils 305 may be used as shown in FIG. 8C.

Next, one mode of a structure of a thin film integrated circuit and adisplay device in a noncontanct-type IC card is described. FIG. 9 showsa block diagram of a thin film integrated circuit 401 and a displaydevice 402 that are provided for an IC card of the present invention.

Reference number 400 denotes an input antenna coil, 413 denotes anoutput antenna coil. 403 a denotes an input interface, 403 b denotes anoutput interface. It is noted that the number of each antenna coil isnot limited to the number shown in FIG. 9.

A CPU 404, a ROM 405, a RAM 406, an EEPROM 407, a coprocessor 408, and acontroller 409 are provided for the thin film integrated circuit 401shown in FIG. 9, as the case of FIG. 7. A pixel portion 410, a scanningline driver circuit 411, and a signal line driver circuit 412 areprovided for the display device 402.

AC power supply voltage or various signals inputted from a terminalequipment by the input antenna coil 400 are waveform-shaped or made adirect current in the input interface 403 a, and then supplied to eachcircuit. An output signal outputted from the thin film integratedcircuit 401 is modulated in the output interface 403 b, and sent to theterminal equipment by the output antenna coil 413.

FIG. 10A shows a more detailed structure of the input interface 403 a. Arectification circuit 420 and a demodulation circuit 421 are providedfor the input interface 403 a shown in FIG. 10A. AC power supply voltageinputted from the input antenna coil 400 is rectified in therectification circuit 420 and supplied to each circuit within the thinfilm integrated circuit 401 as DC power supply voltage. Each of ACsignals inputted from the input antenna coil 400 is demodulated in thedemodulation circuit 421 and supplied to each circuit within the thinfilm integrated circuit 401.

FIG. 10B shows a more detailed structure of the output interface 403 b.A modulation circuit 423 and an amplifier 424 are provided for theoutput interface 403 b shown in FIG. 10B. Various signals that areinputted to the output interface 403 b from each circuit within the thinfilm integrated circuit 401 are modulated in the modulation circuit 423,amplified or buffer-amplified in the amplifier 424, and then, sent tothe terminal equipment from the output antenna coil 413.

In this embodiment mode, an example of a noncontact type using a coilantenna is shown. However, the noncontact type IC card is not limitedthereto. A light emitting element, an optical sensor or the like may beused for sending and receiving data.

Further, in this embodiment mode, an example of supplying a power supplyvoltage from a reader/writer by an antenna coil or a connectionterminal. However, the present invention is not limited thereto. Forexample, an ultrathin type battery such as a lithium battery may beincorporated, or a solar battery may be provided.

As described above, a less expensive and larger glass substrate than asilicon wafer can be used in the present invention, therebymass-producing thin film integrated circuits at lower cost and withhigher throughput, and reducing the manufacturing cost extremely. Asubstrate can be used repeatedly, and thus the cost can be reduced.

According to the present invention, it is possible to provide a largernumber of thin film integrated circuits having a larger memory capacityor a larger circuit scale within the limited area, since a thin filmintegrated circuit that is extremely thin can be formed according to thepresent invention. The formed display device can be thin enough to beprovided for the IC card that is from 0.05 mm to 1 mm thick.Accordingly, it is possible to realize multi-functionality of the ICcard without preventing an IC card from becoming smaller and lighter.

A thin film integrated circuit or a display device can be bonded inaccordance with a shape of a printed wiring board, and thus, there is alot of flexibility for a shape of an IC card. Therefore, for example, itis possible to form an IC card into a shape having a curved surface,which can be attached to a columnar bottle.

Embodiments

Hereinafter, embodiments of the present invention are described.

Embodiment 1

In this embodiment, electrical connection between an interposer providedfor a contact type IC card and a thin film integrated circuit isdescribed.

FIG. 11A is an oblique perspective figure showing a cross-sectionalstructure of the thin film integrated circuit connected to theinterposer by a wire-bonding method. Reference number 601 denotes aninterposer, 602 denotes a thin film integrated circuit. The thin filmintegrated circuit 602 is mounted over the interposer 601 by an adhesiveagent 604 for mounting.

A connection terminal 605 is provided for a reverse side of the faceover which the thin film integrated circuit 602 is mounted in theinterposer 601 shown in FIG. 11A. A pad 606 provided for the interposer601 is electrically connected to the connection terminal 605 via acontact hole provided for the interposer 601.

In this embodiment, the connection terminal 605 is electricallyconnected to the pad 606 directly through the contact hole. However, forexample, multi-layered wirings may be provided within the interposer 601and the electrical connection may be conducted by the wirings.

In FIG. 11A, the thin film integrated circuit 602 is electricallyconnected to the pad 606 by a wire 607. FIG. 11B is a cross sectionalview of a package shown in FIG. 11A. A semiconductor element 609 isprovided for the thin film integrated circuit 602. A pad 608 for thethin film integrated circuit is provided for the side opposite to theside of the thin film integrated circuit 602 for which the interposer601 is provided. The pad 608 is electrically connected to thesemiconductor element 609. The pad 608 for the thin film integratedcircuit is electrically connected to the pad 606 formed over theinterposer 601 by the wire 607.

FIG. 11C is a cross sectional view of the thin film integrated circuitthat is connected to the interposer by a flip chip method. A solder ball627 is provided for a thin film integrated circuit 622 in a packageshown in FIG. 11C. The solder ball 627 is provided for the side of theinterposer 621 of the thin film integrated circuit 622, and connected toa pad 628 similarly provided for the thin film integrated circuit 622. Asemiconductor element 629 provided for the thin film integrated circuit622 is connected to the pad 628. When a TFT is used as the semiconductorelement 629, the pad 628 may be formed of the same conductive film asthat of a gate electrode of the TFT.

The solder ball 627 is connected to the pad 626 provided for theinterposer 621. In FIG. 11C, an underfilling 624 is provided to fill aspace between the solder balls 627. A connection terminal 625 of theinterposer 621 is provided for the side opposite to the side over whichthe thin film integrated circuit 622 of the interposer 621 is mounted.The pad 626 provided for the interposer 621 is electrically connected tothe connection terminal 625 through a contact hole provided for theinterposer 621.

The flip chip method is suitable for a connection of a thin filmintegrated circuit having a lot of terminals, since a pitch between padsis kept wider relatively than when a wire bonding method is employed,even if the number of pads to be connected increases.

FIG. 11D is a cross sectional view of a thin film integrated circuitlaminated by a flip chip method. Two thin film integrated circuits 630and 631 are laminated over an interposer 633 in FIG. 11D. A pad 636provided for the interposer 633 is electrically connected to the thinfilm integrated circuit 630 with a solder ball 634. The thin filmintegrated circuit 631 is also electrically connected to the thin filmintegrated circuit 630 with a solder ball 632.

FIGS. 11A to 11D show an example of mounting the thin film integratedcircuits over the interposer as a bare chip. In the present invention,the thin film integrated circuits may be packaged and then, mounted overthe interposer. In this case, the electrical connection between the thinfilm integrated circuit and the interposer may be conducted with asolder ball, a wire, or the combination of the both.

For the method of connecting the solder ball and the pad, variousmethods such as thermocompression or thermocompression added withultrasonic vibration can be used. An underfilling may be provided tofill gaps between solder balls after the thermocompression for enhancingthe mechanical strength of connecting portion and the coefficient ofthermal diffusivity of heat generated in the package. The underfilling,although it is not always necessary to be used, can prevent poorelectrical connection due to stress caused by the mismatch coefficientof thermal expansion of a printed wiring board or the interposer and thethin film integrated circuit. In the case of bonding bythermocompression added with ultrasonic vibration, poor electricalconnection can be prevented compared with the case of bonding solely bythermocompression. Especially, it is efficient for the case where aconnection point between the thin film integrated circuit and theprinted wiring board or the interposer are more than 100.

Embodiment 2

In this embodiment, a specific example of using an IC card of thepresent invention as an ATM card is described.

As shown in FIG. 12, image data of a bank depositor's face is memorizedin a ROM provided for a thin film integrated circuit of an ATM card whenhe/she opens an account in a financial institution such as a bank.Forgery such as changing the photograph of a human face can be preventedby memorizing the data thereof in the ROM. The ATM card is provided forthe bank depositor, and then he/she can begin to use the ATM card.

An ATM card is used for dealings at an ATM (automated teller machine) ora window. When dealing such as withdrawing, depositing, or transferringcash is done, details such as deposit balance or dealing date isrequired to be memorized in an EEPROM provided for a thin filmintegrated circuit of an ATM card.

After the dealing, details such as deposit balance or dealing date maybe displayed in a pixel portion of the ATM card, and the display may beprogrammed to vanish after a given time. During the dealing, a paymentsuch as an automatic draft from an account by transferring cashautomatically that is performed without an ATM card may beentered-account using the IC card and confirmed in the pixel portion.

Before a payment is performed directly from an account without dealingin cash using a bank ATM card like a debit card (R), information about abank balance is got out from a host computer of a bank by using aterminal equipment used in the payment, and the information of the bankbalance may be displayed in the pixel portion of the IC card. When thebank balance is displayed with the terminal equipment, there is a riskof someone's steeling a glance at it from behind. However, an IC carduser can confirm the bank balance without being stolen glance at, bydisplaying the bank balance in the pixel portion of the IC card. Sinceit is possible to confirm the bank balance with terminal equipment forpayment placed in a shop, troublesome chores such as balance inquiry andaccount book updating at a bank window or ATM can be avoided.

An IC card of the present invention is not limited to an ATM card. TheIC card of the present invention may be applied to a train pass or aprepaid card, and information about remaining balance may be displayedin a pixel portion.

Embodiment 3

In this embodiment, a case in which a plurality of liquid crystaldisplay devices is manufactured from one substrate is described.

FIG. 13A is a top view of a substrate when a plurality of liquid crystaldisplay devices is manufactured at the same time over a first substrate1301. A sealing material 1302 to surround an area in which a liquidcrystal is to be sealed is laid out and formed over the first substrate1301 over which an alignment film is formed. A liquid crystal 1303 isdripped to the area surrounded by the sealing material 1302.

FIG. 13B is a cross sectional view along a broken line A-A′ in FIG. 13A.As shown in FIG. 13B, the liquid crystal 1303 is dripped to the areasurrounded by the sealing material 1302. Next, as shown in FIG. 13C, anopposite substrate 1304 is pressure-bonded so that the liquid crystal1303 can be sealed within the area surrounded by the sealing material1302.

After pressure-bonding the opposite substrate, as shown in FIG. 13D, thefirst substrate 1301 is peeled off and removed. After that, a plasticsubstrate 1305 is bonded as shown in FIG. 13E. Dicing is performed in aposition of a dotted line, and then display devices are separated fromone another as shown in FIG. 13F.

In this embodiment, a case of a liquid crystal display device isdescribed. However, the present invention is not limited thereto. Aplurality of light emitting devices or other display devices can bemanufactured at the same time.

FIGS. 14A and 14B are cross sectional views of a liquid crystal displayof this embodiment. A columnar spacer 1401 is provided for a pixel in aliquid crystal display device shown in FIG. 14A. Adhesion between anopposite substrate 1402 and a substrate 1403 on the side of elements isenhanced by the columnar spacer 1401. This makes it possible to preventa semiconductor element in the outside of the area overlapping with asealing material from remaining on the side of the first substrate, whenthe first substrate is peeled off.

FIG. 14B is a cross sectional view of a liquid crystal display deviceusing nematic liquid crystal, smectic liquid crystal, ferroelectricliquid crystal, or PDLC (polymer dispersed liquid crystal) in which theabove described liquid crystal is included in polymer resin. Adhesionbetween the opposite substrate 1402 and the substrate 1403 on the sideof elements is enhanced by PDLC 1404. This makes it possible to preventa semiconductor element in the outside of the area overlapping with asealing material from remaining on the side of the first substrate, whenthe first substrate is peeled off.

As described above, a glass substrate that is less expensive and largerthan a silicon wafer can be used, and thus, thin film integratedcircuits can be mass-produced at lower cost and with higher throughputaccording to the present invention. As a result, a manufacturing costcan be reduced dramatically. Further, it is possible to use a substraterepeatedly, thereby reducing the cost.

According to the present invention, a thin film integrated circuit thatis ultrathin can be manufactured. It is also possible to provide alarger number of thin film integrated circuits having a larger memorycapacity or a larger circuit scale within the limited area. A displaydevice can be formed to be thin enough to be provided for an IC cardhaving a thickness of from 0.05 mm through 1 mm. Accordingly,multi-functionality of the IC card can be realized without preventing anIC card from becoming smaller and lighter.

A thin film integrated circuit or a display device can be bonded inaccordance with a shape of a printed wiring board, and thus, there is alot of flexibility for a shape of an IC card. Therefore, for example, itis possible to form an IC card into a shape having a curved surface,which can be attached to a columnar bottle.

1. A method for manufacturing an article comprising: forming a metalfilm over a substrate; forming a metal oxide film by oxidizing a surfaceof the metal film; selectively removing the metal film formed in an edgeportion of the substrate; forming a base film over the metal oxide film;forming a semiconductor element over the base film; and separating thesemiconductor element and the base film from the substrate by physicalmeans.
 2. The method for manufacturing the article according to claim 1,further comprising forming an insulating film on the substrate.
 3. Themethod for manufacturing the article according to claim 1, wherein themetal film includes tungsten.
 4. The method for manufacturing thearticle according to claim 1, wherein the semiconductor elementcomprises a thin film transistor.
 5. The method for manufacturing thearticle according to claim 1, wherein the semiconductor elementcomprises a memory element.
 6. The method for manufacturing the articleaccording to claim 1, wherein the article is a card having a thicknessof from 0.05 mm to 1 mm.
 7. The method for manufacturing the articleaccording to claim 1, wherein the article further comprises an antenna.8. A method for manufacturing an article comprising: forming a metalfilm over a substrate; forming a metal oxide film by oxidizing a surfaceof the metal film; selectively removing the metal film formed in an edgeportion of the substrate; forming a base film over the metal oxide film;forming a semiconductor element over the base film; forming a pixelelectrode electrically connected to the semiconductor element; andseparating the pixel electrode, the semiconductor element and the basefilm from the substrate by physical means.
 9. The method formanufacturing the article according to claim 8, further comprisingforming an insulating film on the substrate.
 10. The method formanufacturing the article according to claim 8, wherein the metal filmincludes tungsten.
 11. The method for manufacturing the articleaccording to claim 8, wherein the semiconductor element comprises a thinfilm transistor.
 12. The method for manufacturing the article accordingto claim 8, wherein the article is a card having a thickness of from0.05 mm to 1 mm.
 13. The method for manufacturing the article accordingto claim 8, wherein the article further comprises an antenna.
 14. Themethod for manufacturing the article according to claim 8, wherein thearticle is a display device.
 15. The method for manufacturing thearticle according to claim 14, wherein the display device is a liquidcrystal display device.
 16. A method for manufacturing an articlecomprising: forming a metal film over a substrate; forming an oxide filmover the metal film wherein a metal oxide film is formed between themetal film and the oxide film; selectively removing the metal filmformed in an edge portion of the substrate; forming a base film over themetal oxide film; forming a semiconductor element over the base film;forming a pixel electrode electrically connected to the semiconductorelement; and separating the pixel electrode, the semiconductor elementand the base film from the substrate by physical means.
 17. The methodfor manufacturing the article according to claim 16, further comprisingforming an insulating film on the substrate.
 18. The method formanufacturing the article according to claim 16, wherein the metal filmincludes tungsten.
 19. The method for manufacturing the articleaccording to claim 16, wherein the semiconductor element comprises athin film transistor.
 20. The method for manufacturing the articleaccording to claim 16, wherein the article is a card having a thicknessof from 0.05 mm to 1 mm.
 21. The method for manufacturing the articleaccording to claim 16, wherein the article further comprises an antenna.22. The method for manufacturing the article according to claim 16,wherein the article is a display device.
 23. The method formanufacturing the article according to claim 22, wherein the displaydevice is a liquid crystal display device.